module/zfs/spa_config.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
  25  * Copyright (c) 2013 by Delphix. All rights reserved.
  26  */
  27
  28 #include <sys/spa.h>
  29 #include <sys/fm/fs/zfs.h>
  30 #include <sys/spa_impl.h>
  31 #include <sys/nvpair.h>
  32 #include <sys/uio.h>
  33 #include <sys/fs/zfs.h>
  34 #include <sys/vdev_impl.h>
  35 #include <sys/zfs_ioctl.h>
  36 #include <sys/systeminfo.h>
  37 #include <sys/sunddi.h>
  38 #include <sys/zfeature.h>
  39 #ifdef _KERNEL
  40 #include <sys/kobj.h>
  41 #include <sys/zone.h>
  42 #endif
  43
  44 /*
  45  * Pool configuration repository.
  46  *
  47  * Pool configuration is stored as a packed nvlist on the filesystem.  By
  48  * default, all pools are stored in /etc/zfs/zpool.cache and loaded on boot
  49  * (when the ZFS module is loaded).  Pools can also have the 'cachefile'
  50  * property set that allows them to be stored in an alternate location until
  51  * the control of external software.
  52  *
  53  * For each cache file, we have a single nvlist which holds all the
  54  * configuration information.  When the module loads, we read this information
  55  * from /etc/zfs/zpool.cache and populate the SPA namespace.  This namespace is
  56  * maintained independently in spa.c.  Whenever the namespace is modified, or
  57  * the configuration of a pool is changed, we call spa_config_sync(), which
  58  * walks through all the active pools and writes the configuration to disk.
  59  */
  60
  61 static uint64_t spa_config_generation = 1;
  62
  63 /*
  64  * This can be overridden in userland to preserve an alternate namespace for
  65  * userland pools when doing testing.
  66  */
  67 char *spa_config_path = ZPOOL_CACHE;
  68 int zfs_autoimport_disable = 1;
  69
  70 /*
  71  * Called when the module is first loaded, this routine loads the configuration
  72  * file into the SPA namespace.  It does not actually open or load the pools; it
  73  * only populates the namespace.
  74  */
  75 void
  76 spa_config_load(void)
  77 {
  78         void *buf = NULL;
  79         nvlist_t *nvlist, *child;
  80         nvpair_t *nvpair;
  81         char *pathname;
  82         struct _buf *file;
  83         uint64_t fsize;
  84
  85 #ifdef _KERNEL
  86         if (zfs_autoimport_disable)
  87                 return;
  88 #endif
  89
  90         /*
  91          * Open the configuration file.
  92          */
  93         pathname = kmem_alloc(MAXPATHLEN, KM_SLEEP);
  94
  95         (void) snprintf(pathname, MAXPATHLEN, "%s%s",
  96             (rootdir != NULL) ? "./" : "", spa_config_path);
  97
  98         file = kobj_open_file(pathname);
  99
 100         kmem_free(pathname, MAXPATHLEN);
 101
 102         if (file == (struct _buf *)-1)
 103                 return;
 104
 105         if (kobj_get_filesize(file, &fsize) != 0)
 106                 goto out;
 107
 108         buf = kmem_alloc(fsize, KM_SLEEP);
 109
 110         /*
 111          * Read the nvlist from the file.
 112          */
 113         if (kobj_read_file(file, buf, fsize, 0) < 0)
 114                 goto out;
 115
 116         /*
 117          * Unpack the nvlist.
 118          */
 119         if (nvlist_unpack(buf, fsize, &nvlist, KM_SLEEP) != 0)
 120                 goto out;
 121
 122         /*
 123          * Iterate over all elements in the nvlist, creating a new spa_t for
 124          * each one with the specified configuration.
 125          */
 126         mutex_enter(&spa_namespace_lock);
 127         nvpair = NULL;
 128         while ((nvpair = nvlist_next_nvpair(nvlist, nvpair)) != NULL) {
 129                 if (nvpair_type(nvpair) != DATA_TYPE_NVLIST)
 130                         continue;
 131
 132                 VERIFY(nvpair_value_nvlist(nvpair, &child) == 0);
 133
 134                 if (spa_lookup(nvpair_name(nvpair)) != NULL)
 135                         continue;
 136                 (void) spa_add(nvpair_name(nvpair), child, NULL);
 137         }
 138         mutex_exit(&spa_namespace_lock);
 139
 140         nvlist_free(nvlist);
 141
 142 out:
 143         if (buf != NULL)
 144                 kmem_free(buf, fsize);
 145
 146         kobj_close_file(file);
 147 }
 148
 149 static int
 150 spa_config_write(spa_config_dirent_t *dp, nvlist_t *nvl)
 151 {
 152         size_t buflen;
 153         char *buf;
 154         vnode_t *vp;
 155         int oflags = FWRITE | FTRUNC | FCREAT | FOFFMAX;
 156         char *temp;
 157         int err;
 158
 159         /*
 160          * If the nvlist is empty (NULL), then remove the old cachefile.
 161          */
 162         if (nvl == NULL) {
 163                 err = vn_remove(dp->scd_path, UIO_SYSSPACE, RMFILE);
 164                 return (err);
 165         }
 166
 167         /*
 168          * Pack the configuration into a buffer.
 169          */
 170         VERIFY(nvlist_size(nvl, &buflen, NV_ENCODE_XDR) == 0);
 171
 172         buf = vmem_alloc(buflen, KM_SLEEP);
 173         temp = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
 174
 175         VERIFY(nvlist_pack(nvl, &buf, &buflen, NV_ENCODE_XDR,
 176             KM_SLEEP) == 0);
 177
 178 #if defined(__linux__) && defined(_KERNEL)
 179         /*
 180          * Write the configuration to disk.  Due to the complexity involved
 181          * in performing a rename from within the kernel the file is truncated
 182          * and overwritten in place.  In the event of an error the file is
 183          * unlinked to make sure we always have a consistent view of the data.
 184          */
 185         err = vn_open(dp->scd_path, UIO_SYSSPACE, oflags, 0644, &vp, 0, 0);
 186         if (err == 0) {
 187                 err = vn_rdwr(UIO_WRITE, vp, buf, buflen, 0,
 188                     UIO_SYSSPACE, 0, RLIM64_INFINITY, kcred, NULL);
 189                 if (err == 0)
 190                         err = VOP_FSYNC(vp, FSYNC, kcred, NULL);
 191
 192                 (void) VOP_CLOSE(vp, oflags, 1, 0, kcred, NULL);
 193
 194                 if (err)
 195                         (void) vn_remove(dp->scd_path, UIO_SYSSPACE, RMFILE);
 196         }
 197 #else
 198         /*
 199          * Write the configuration to disk.  We need to do the traditional
 200          * 'write to temporary file, sync, move over original' to make sure we
 201          * always have a consistent view of the data.
 202          */
 203         (void) snprintf(temp, MAXPATHLEN, "%s.tmp", dp->scd_path);
 204
 205         err = vn_open(temp, UIO_SYSSPACE, oflags, 0644, &vp, CRCREAT, 0);
 206         if (err == 0) {
 207                 err = vn_rdwr(UIO_WRITE, vp, buf, buflen, 0, UIO_SYSSPACE,
 208                     0, RLIM64_INFINITY, kcred, NULL);
 209                 if (err == 0)
 210                         err = VOP_FSYNC(vp, FSYNC, kcred, NULL);
 211                 if (err == 0)
 212                         err = vn_rename(temp, dp->scd_path, UIO_SYSSPACE);
 213                 (void) VOP_CLOSE(vp, oflags, 1, 0, kcred, NULL);
 214         }
 215
 216         (void) vn_remove(temp, UIO_SYSSPACE, RMFILE);
 217 #endif
 218
 219         vmem_free(buf, buflen);
 220         kmem_free(temp, MAXPATHLEN);
 221         return (err);
 222 }
 223
 224 /*
 225  * Synchronize pool configuration to disk.  This must be called with the
 226  * namespace lock held. Synchronizing the pool cache is typically done after
 227  * the configuration has been synced to the MOS. This exposes a window where
 228  * the MOS config will have been updated but the cache file has not. If
 229  * the system were to crash at that instant then the cached config may not
 230  * contain the correct information to open the pool and an explicity import
 231  * would be required.
 232  */
 233 void
 234 spa_config_sync(spa_t *target, boolean_t removing, boolean_t postsysevent)
 235 {
 236         spa_config_dirent_t *dp, *tdp;
 237         nvlist_t *nvl;
 238         char *pool_name;
 239         boolean_t ccw_failure;
 240         int error = 0;
 241
 242         ASSERT(MUTEX_HELD(&spa_namespace_lock));
 243
 244         if (rootdir == NULL || !(spa_mode_global & FWRITE))
 245                 return;
 246
 247         /*
 248          * Iterate over all cachefiles for the pool, past or present.  When the
 249          * cachefile is changed, the new one is pushed onto this list, allowing
 250          * us to update previous cachefiles that no longer contain this pool.
 251          */
 252         ccw_failure = B_FALSE;
 253         for (dp = list_head(&target->spa_config_list); dp != NULL;
 254             dp = list_next(&target->spa_config_list, dp)) {
 255                 spa_t *spa = NULL;
 256                 if (dp->scd_path == NULL)
 257                         continue;
 258
 259                 /*
 260                  * Iterate over all pools, adding any matching pools to 'nvl'.
 261                  */
 262                 nvl = NULL;
 263                 while ((spa = spa_next(spa)) != NULL) {
 264                         /*
 265                          * Skip over our own pool if we're about to remove
 266                          * ourselves from the spa namespace or any pool that
 267                          * is readonly. Since we cannot guarantee that a
 268                          * readonly pool would successfully import upon reboot,
 269                          * we don't allow them to be written to the cache file.
 270                          */
 271                         if ((spa == target && removing) ||
 272                             !spa_writeable(spa))
 273                                 continue;
 274
 275                         mutex_enter(&spa->spa_props_lock);
 276                         tdp = list_head(&spa->spa_config_list);
 277                         if (spa->spa_config == NULL ||
 278                             tdp->scd_path == NULL ||
 279                             strcmp(tdp->scd_path, dp->scd_path) != 0) {
 280                                 mutex_exit(&spa->spa_props_lock);
 281                                 continue;
 282                         }
 283
 284                         if (nvl == NULL)
 285                                 VERIFY(nvlist_alloc(&nvl, NV_UNIQUE_NAME,
 286                                     KM_SLEEP) == 0);
 287
 288                         if (spa->spa_import_flags & ZFS_IMPORT_TEMP_NAME) {
 289                                 VERIFY0(nvlist_lookup_string(spa->spa_config,
 290                                         ZPOOL_CONFIG_POOL_NAME, &pool_name));
 291                         } else
 292                                 pool_name = spa_name(spa);
 293
 294                         VERIFY(nvlist_add_nvlist(nvl, pool_name,
 295                             spa->spa_config) == 0);
 296                         mutex_exit(&spa->spa_props_lock);
 297                 }
 298
 299                 error = spa_config_write(dp, nvl);
 300                 if (error != 0)
 301                         ccw_failure = B_TRUE;
 302                 nvlist_free(nvl);
 303         }
 304
 305         if (ccw_failure) {
 306                 /*
 307                  * Keep trying so that configuration data is
 308                  * written if/when any temporary filesystem
 309                  * resource issues are resolved.
 310                  */
 311                 if (target->spa_ccw_fail_time == 0) {
 312                         zfs_ereport_post(FM_EREPORT_ZFS_CONFIG_CACHE_WRITE,
 313                             target, NULL, NULL, 0, 0);
 314                 }
 315                 target->spa_ccw_fail_time = gethrtime();
 316                 spa_async_request(target, SPA_ASYNC_CONFIG_UPDATE);
 317         } else {
 318                 /*
 319                  * Do not rate limit future attempts to update
 320                  * the config cache.
 321                  */
 322                 target->spa_ccw_fail_time = 0;
 323         }
 324
 325         /*
 326          * Remove any config entries older than the current one.
 327          */
 328         dp = list_head(&target->spa_config_list);
 329         while ((tdp = list_next(&target->spa_config_list, dp)) != NULL) {
 330                 list_remove(&target->spa_config_list, tdp);
 331                 if (tdp->scd_path != NULL)
 332                         spa_strfree(tdp->scd_path);
 333                 kmem_free(tdp, sizeof (spa_config_dirent_t));
 334         }
 335
 336         spa_config_generation++;
 337
 338         if (postsysevent)
 339                 spa_event_notify(target, NULL, FM_EREPORT_ZFS_CONFIG_SYNC);
 340 }
 341
 342 /*
 343  * Sigh.  Inside a local zone, we don't have access to /etc/zfs/zpool.cache,
 344  * and we don't want to allow the local zone to see all the pools anyway.
 345  * So we have to invent the ZFS_IOC_CONFIG ioctl to grab the configuration
 346  * information for all pool visible within the zone.
 347  */
 348 nvlist_t *
 349 spa_all_configs(uint64_t *generation)
 350 {
 351         nvlist_t *pools;
 352         spa_t *spa = NULL;
 353
 354         if (*generation == spa_config_generation)
 355                 return (NULL);
 356
 357         VERIFY(nvlist_alloc(&pools, NV_UNIQUE_NAME, KM_SLEEP) == 0);
 358
 359         mutex_enter(&spa_namespace_lock);
 360         while ((spa = spa_next(spa)) != NULL) {
 361                 if (INGLOBALZONE(curproc) ||
 362                     zone_dataset_visible(spa_name(spa), NULL)) {
 363                         mutex_enter(&spa->spa_props_lock);
 364                         VERIFY(nvlist_add_nvlist(pools, spa_name(spa),
 365                             spa->spa_config) == 0);
 366                         mutex_exit(&spa->spa_props_lock);
 367                 }
 368         }
 369         *generation = spa_config_generation;
 370         mutex_exit(&spa_namespace_lock);
 371
 372         return (pools);
 373 }
 374
 375 void
 376 spa_config_set(spa_t *spa, nvlist_t *config)
 377 {
 378         mutex_enter(&spa->spa_props_lock);
 379         nvlist_free(spa->spa_config);
 380         spa->spa_config = config;
 381         mutex_exit(&spa->spa_props_lock);
 382 }
 383
 384 /*
 385  * Generate the pool's configuration based on the current in-core state.
 386  *
 387  * We infer whether to generate a complete config or just one top-level config
 388  * based on whether vd is the root vdev.
 389  */
 390 nvlist_t *
 391 spa_config_generate(spa_t *spa, vdev_t *vd, uint64_t txg, int getstats)
 392 {
 393         nvlist_t *config, *nvroot;
 394         vdev_t *rvd = spa->spa_root_vdev;
 395         unsigned long hostid = 0;
 396         boolean_t locked = B_FALSE;
 397         uint64_t split_guid;
 398         char *pool_name;
 399
 400         if (vd == NULL) {
 401                 vd = rvd;
 402                 locked = B_TRUE;
 403                 spa_config_enter(spa, SCL_CONFIG | SCL_STATE, FTAG, RW_READER);
 404         }
 405
 406         ASSERT(spa_config_held(spa, SCL_CONFIG | SCL_STATE, RW_READER) ==
 407             (SCL_CONFIG | SCL_STATE));
 408
 409         /*
 410          * If txg is -1, report the current value of spa->spa_config_txg.
 411          */
 412         if (txg == -1ULL)
 413                 txg = spa->spa_config_txg;
 414
 415         /*
 416          * Originally, users had to handle spa namespace collisions by either
 417          * exporting the already imported pool or by specifying a new name for
 418          * the pool with a conflicting name. In the case of root pools from
 419          * virtual guests, neither approach to collision resolution is
 420          * reasonable. This is addressed by extending the new name syntax with
 421          * an option to specify that the new name is temporary. When specified,
 422          * ZFS_IMPORT_TEMP_NAME will be set in spa->spa_import_flags to tell us
 423          * to use the previous name, which we do below.
 424          */
 425         if (spa->spa_import_flags & ZFS_IMPORT_TEMP_NAME) {
 426                 VERIFY0(nvlist_lookup_string(spa->spa_config,
 427                         ZPOOL_CONFIG_POOL_NAME, &pool_name));
 428         } else
 429                 pool_name = spa_name(spa);
 430
 431         VERIFY(nvlist_alloc(&config, NV_UNIQUE_NAME, KM_SLEEP) == 0);
 432
 433         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VERSION,
 434             spa_version(spa)) == 0);
 435         VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME,
 436             pool_name) == 0);
 437         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE,
 438             spa_state(spa)) == 0);
 439         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_TXG,
 440             txg) == 0);
 441         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_GUID,
 442             spa_guid(spa)) == 0);
 443         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_ERRATA,
 444             spa->spa_errata) == 0);
 445         VERIFY(spa->spa_comment == NULL || nvlist_add_string(config,
 446             ZPOOL_CONFIG_COMMENT, spa->spa_comment) == 0);
 447
 448
 449 #ifdef  _KERNEL
 450         hostid = zone_get_hostid(NULL);
 451 #else   /* _KERNEL */
 452         /*
 453          * We're emulating the system's hostid in userland, so we can't use
 454          * zone_get_hostid().
 455          */
 456         (void) ddi_strtoul(hw_serial, NULL, 10, &hostid);
 457 #endif  /* _KERNEL */
 458         if (hostid != 0) {
 459                 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_HOSTID,
 460                     hostid) == 0);
 461         }
 462         VERIFY0(nvlist_add_string(config, ZPOOL_CONFIG_HOSTNAME,
 463             utsname()->nodename));
 464
 465         if (vd != rvd) {
 466                 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_TOP_GUID,
 467                     vd->vdev_top->vdev_guid) == 0);
 468                 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_GUID,
 469                     vd->vdev_guid) == 0);
 470                 if (vd->vdev_isspare)
 471                         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_IS_SPARE,
 472                             1ULL) == 0);
 473                 if (vd->vdev_islog)
 474                         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_IS_LOG,
 475                             1ULL) == 0);
 476                 vd = vd->vdev_top;              /* label contains top config */
 477         } else {
 478                 /*
 479                  * Only add the (potentially large) split information
 480                  * in the mos config, and not in the vdev labels
 481                  */
 482                 if (spa->spa_config_splitting != NULL)
 483                         VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_SPLIT,
 484                             spa->spa_config_splitting) == 0);
 485         }
 486
 487         /*
 488          * Add the top-level config.  We even add this on pools which
 489          * don't support holes in the namespace.
 490          */
 491         vdev_top_config_generate(spa, config);
 492
 493         /*
 494          * If we're splitting, record the original pool's guid.
 495          */
 496         if (spa->spa_config_splitting != NULL &&
 497             nvlist_lookup_uint64(spa->spa_config_splitting,
 498             ZPOOL_CONFIG_SPLIT_GUID, &split_guid) == 0) {
 499                 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_SPLIT_GUID,
 500                     split_guid) == 0);
 501         }
 502
 503         nvroot = vdev_config_generate(spa, vd, getstats, 0);
 504         VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, nvroot) == 0);
 505         nvlist_free(nvroot);
 506
 507         /*
 508          * Store what's necessary for reading the MOS in the label.
 509          */
 510         VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_FEATURES_FOR_READ,
 511             spa->spa_label_features) == 0);
 512
 513         if (getstats && spa_load_state(spa) == SPA_LOAD_NONE) {
 514                 ddt_histogram_t *ddh;
 515                 ddt_stat_t *dds;
 516                 ddt_object_t *ddo;
 517
 518                 ddh = kmem_zalloc(sizeof (ddt_histogram_t), KM_SLEEP);
 519                 ddt_get_dedup_histogram(spa, ddh);
 520                 VERIFY(nvlist_add_uint64_array(config,
 521                     ZPOOL_CONFIG_DDT_HISTOGRAM,
 522                     (uint64_t *)ddh, sizeof (*ddh) / sizeof (uint64_t)) == 0);
 523                 kmem_free(ddh, sizeof (ddt_histogram_t));
 524
 525                 ddo = kmem_zalloc(sizeof (ddt_object_t), KM_SLEEP);
 526                 ddt_get_dedup_object_stats(spa, ddo);
 527                 VERIFY(nvlist_add_uint64_array(config,
 528                     ZPOOL_CONFIG_DDT_OBJ_STATS,
 529                     (uint64_t *)ddo, sizeof (*ddo) / sizeof (uint64_t)) == 0);
 530                 kmem_free(ddo, sizeof (ddt_object_t));
 531
 532                 dds = kmem_zalloc(sizeof (ddt_stat_t), KM_SLEEP);
 533                 ddt_get_dedup_stats(spa, dds);
 534                 VERIFY(nvlist_add_uint64_array(config,
 535                     ZPOOL_CONFIG_DDT_STATS,
 536                     (uint64_t *)dds, sizeof (*dds) / sizeof (uint64_t)) == 0);
 537                 kmem_free(dds, sizeof (ddt_stat_t));
 538         }
 539
 540         if (locked)
 541                 spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG);
 542
 543         return (config);
 544 }
 545
 546 /*
 547  * Update all disk labels, generate a fresh config based on the current
 548  * in-core state, and sync the global config cache (do not sync the config
 549  * cache if this is a booting rootpool).
 550  */
 551 void
 552 spa_config_update(spa_t *spa, int what)
 553 {
 554         vdev_t *rvd = spa->spa_root_vdev;
 555         uint64_t txg;
 556         int c;
 557
 558         ASSERT(MUTEX_HELD(&spa_namespace_lock));
 559
 560         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
 561         txg = spa_last_synced_txg(spa) + 1;
 562         if (what == SPA_CONFIG_UPDATE_POOL) {
 563                 vdev_config_dirty(rvd);
 564         } else {
 565                 /*
 566                  * If we have top-level vdevs that were added but have
 567                  * not yet been prepared for allocation, do that now.
 568                  * (It's safe now because the config cache is up to date,
 569                  * so it will be able to translate the new DVAs.)
 570                  * See comments in spa_vdev_add() for full details.
 571                  */
 572                 for (c = 0; c < rvd->vdev_children; c++) {
 573                         vdev_t *tvd = rvd->vdev_child[c];
 574                         if (tvd->vdev_ms_array == 0)
 575                                 vdev_metaslab_set_size(tvd);
 576                         vdev_expand(tvd, txg);
 577                 }
 578         }
 579         spa_config_exit(spa, SCL_ALL, FTAG);
 580
 581         /*
 582          * Wait for the mosconfig to be regenerated and synced.
 583          */
 584         txg_wait_synced(spa->spa_dsl_pool, txg);
 585
 586         /*
 587          * Update the global config cache to reflect the new mosconfig.
 588          */
 589         if (!spa->spa_is_root)
 590                 spa_config_sync(spa, B_FALSE, what != SPA_CONFIG_UPDATE_POOL);
 591
 592         if (what == SPA_CONFIG_UPDATE_POOL)
 593                 spa_config_update(spa, SPA_CONFIG_UPDATE_VDEVS);
 594 }
 595
 596 #if defined(_KERNEL) && defined(HAVE_SPL)
 597 EXPORT_SYMBOL(spa_config_sync);
 598 EXPORT_SYMBOL(spa_config_load);
 599 EXPORT_SYMBOL(spa_all_configs);
 600 EXPORT_SYMBOL(spa_config_set);
 601 EXPORT_SYMBOL(spa_config_generate);
 602 EXPORT_SYMBOL(spa_config_update);
 603
 604 module_param(spa_config_path, charp, 0444);
 605 MODULE_PARM_DESC(spa_config_path, "SPA config file (/etc/zfs/zpool.cache)");
 606
 607 module_param(zfs_autoimport_disable, int, 0644);
 608 MODULE_PARM_DESC(zfs_autoimport_disable, "Disable pool import at module load");
 609
 610 #endif